The inherent torque and vibration characteristics of internal combustion engines make it desirable to provide flexible mounts for such power units. Usually exhaust headers are applied rigidly to the engine for movement therewith, but in many installations the headers must be connected to exhaust tail pipes or other exhaust components that are relatively more constrained than the engine itself. These movement and vibration characteristics present a special problem in connection with the design and fabrication of a connector that will satisfactorily interconnect exhaust header components and other exhaust components for particular installations. When the engine and exhaust system are intended for aircraft use, the problem is even greater. Since the vibration and torque movement patterns for the engine are increased, it is even more desirable that these influences be isolated from the air frame. The high performance characteristics of aircraft engines contribute to a further air safety problem, since a defective connector can burn out in flight to cause a serious fire hazard or to release carbon monoxide gases into the aircraft cabin.
The duty and service requirements for such connectors is increased when exhaust gas turbines are provided for use with aviation engines. In order to minimize precession influences that would act adversely on the rapidly spinning rotor, the turbine is usually mounted on the air frame, and, accordingly, it is relatively restrained when compared with the movement pattern for the engine itself. The engine exhaust gases, at usually higher temperature and pressure, must still be safely and efficiently interconnected to the turbine. Previously used bellows type connectors have a high failure incidence when used for such purpose, and, accordingly, an improved connector is desirable.